11 March 2026

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Assessment of some properties of orthodontic primer after incorporating nanotheobromine

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OBJECTIVES

The study aimed to assess the shear bond strength, changes in FTIR, and degree of conversion for the primer of orthodontic composite after incorporating nanotheobromine powder.

MATERIALS AND METHODS

Twenty-four metal brackets attached to premolars were used to test the shear bond strength. The 3M™ light cure adhesive was modified by incorporating theobromine nanoparticle powder in 10% and 15% concentrations into the primer. Fifteen samples of the primer for the control and the experimental groups were prepared to measure FTIR and the degree of conversion of the primer from monomer to polymer. The differences among groups were analyzed using the ANOVA test at p < 0.05.

RESULTS

The shear bond strength was higher in the group modified with 15% nanotheobromine (20.13 Megapascal) than in the other groups. On the other hand, the experimental nanotheobromine groups yielded no significant change in the degree of conversion when compared to the control. Fourier-transformed infrared spectroscopy also showed no specifically determined chemical changes after nanotheobromine powder incorporation.

CONCLUSION

From the current study, it could be concluded that the experimental composite, particularly the one with 15% nanotheobromine, has good physical and chemical properties, which makes it recommendable for successful use in dental practice.

CLINICAL SIGNIFICANCE

This material improvement will enhance the prevention of white spot lesions around orthodontic brackets.

Authors: Rahma A. Al-Zarki, Ammar Abdulghani, Ali R. Al-Khatib

Source: https://www.dentalcadmos.com/